Physical Identification Flashcards
1
Q
Composition of PI Examiners
A
Forensic Chemical Officers (FOCOs)
➢Criminologists
2
Q
are Licensed Chemical Engineer, Chemist and Registered Medical Technologist
A
Forensic Chemical Officers (FOCOs)
3
Q
Scope of PID Examinations
A
- Ultraviolet examination
- Bullet trajectory examination
- Macro etching examination
- Hair and fiber analysis
- Tool marks examination
- Casting and molding examination
- Microscopic paint analysis
- Presence of Inflammable Substance examination (to BFP)
4
Q
When two objects come in contact with each other there is always an exchange of materials between them.
This type of material exchange – contamination – must be avoided through out the material handling chain, from ______ at the crime scene to the _______ in the laboratory.
A
collection
examination
5
Q
__________WE SHOULD COLLECT ANY AND ALL TYPES OF PHYSICAL EVIDENCE.
A
AS A RULE OF THUMB,
6
Q
is a principle with broad application that is not intended to be strictly accurate or reliable for every situation.
A
A rule of thumb
7
Q
FOUR-WAY LINKAGE THEORY
A
Physical evidence
Victim
Suspect
Crime Scene
8
Q
One of the most common types of physical evidence that an investigator and/or crime scene specialist will encounter will be ______
A
trace evidence.
9
Q
is a generic term for small, often microscopic material.
A
Trace evidence
10
Q
Trace evidence at a crime scene can include _____
A
blood, hair, fibers, glass particles, paint, soil, etc.
11
Q
is a means sanctioned by law in ascertaining the truth of any alleged matter of fact.
A
Evidence –
12
Q
is that one having objective existence that is, in any dimension, size or shape.
A
Physical evidence –
13
Q
is the generic term for evidence that are small, often microscopic materials that may include hairs, fibers, glass particles, foot or tire impression, dust, soil, metal tool marks, tire tracks and paint flakes or chips.
A
Trace evidence –
14
Q
is a filament mostly protein that grows from the follicles found in the dermis.
A
Hair -
15
Q
is the smallest single unit forming the basis of a textile yarn. A _____ is composed of numerous fibers which are spun, twisted, or drawn together to prepare the unit for weaving or knitting. A yarn is sometimes called a _____ by the layman.
A
Fiber or filament -
yarn
thread
16
Q
is a fused mixture of silica, usually in the form of natural sand and two or more alkaline bases such as soda, lime or potash. It also contains quantities of various other element and metals, present as either as incidental impurities in the basic ingredients, or added to them for color, degree of hardness, heat-resistance and other specific purposes.
A
Glass –
17
Q
any object capable of making an impression on another object.
A
Tools –
18
Q
any impression, cut, abrasion, or gouge (scratch, scrape, hollow, mark, cut into) left by a tool after coming in contact with an object
A
Tool marks –
19
Q
determines the point of impact, position of the firearm and the probable caliber of the firearm used.
A
Bullet Trajectory Examination –
20
Q
is a liquid suspension in a solvent carrier into which white or colored pigments and a polymeric resin binder have been combined
A
Paint –
21
Q
is the application of chemical solution on the metal surface where serial numbers is normally located and observing any reaction that may take place.
A
Macro-Etching or Acid-Etching -
22
Q
a series of number that is punched or pressed into a particular item to distinguish it from one another of common type.
A
Serial Numbers –
23
Q
is a radiation of shorter wavelength than the radiation commonly recognized as visible light. It is sometimes known as “_______” because of its invisibility to the eye.
A
UV light –
black light
24
Q
is a filamentous outgrowth of dead cells from the skin found only on mammals
A
Hair
25
Hair uses _____for morphology and microscopic features in the analysis.
comparison microscope or SEM-EDS
26
Purpose of hair examination
1. To determine whether the hair in questioned originated from an animal or human being and the comparison of questioned and known hairs.
2. To ascertain whether one or more individuals could have come into contact with an object.
27
EVIDENTIARY VALUE OF HAIR
* The value of hair as evidence in the criminal cases has been _______
* It is __________ as evidence, but in conjunction with other details, has proven to be an important and essential aid to the investigator.
clearly recognized.
seldom conclusive
28
origin can be of fine to medium coarseness, are generally straight or wavy in appearance, and exhibit colors ranging from blonde to brown black. The hair shafts of _____ vary from round to oval in cross section and have fine to medium-sized, evenly distributed pigment granules
Hairs of Caucasian
| Caucasian hairs
29
origin are regularly coarse, straight, and circular in cross section, with a wider diameter than the hairs of the other racial groups. The outer layer of the hair, the cuticle, is usually significantly thicker than the cuticle of the Negroid and Caucasian hairs and the medulla, or central canal is continuous and wide. ______ hair can have a characteristic reddish appearance as a product of its pigment
Hairs of mongoloid or Asian
Mongoloid
30
origin are regularly curly or kinky, have a flattened cross section, and can appear curly, wavy, or coiled. _______ are larger than those found in Mongoloid and Caucasian hair and are grouped in clumps of different sizes and shapes.
Hairs of Negroid or African
Negroid pigment granules
31
Three parts of hair
Root bulb
Hair shaft
Tip
32
the shape of the root bulb will determine if the hair was pulled by force or not.
Root bulb-
33
contains the most information about the hair.
Hair shaft –
34
will show if the hair is cut, burned or if it has split ends
Tip –
35
Three parts of the hair shaft
Cuticle
Medulla
Cortex
36
is the outer surface of the hair and when viewed under a microscope appears to be composed of scale like flakes, each overlapping the others like the scale of a fish.
Cuticle –
37
is the central canal of the hair shaft. It could be continuous, fragmented, interrupted or absent.
Medulla –
38
contains the color pigmentation of the hair.
Cortex –
39
________hairs, such as a head hair dislodged through combing, display undamaged, club-shaped
roots.
Naturally shed hair
40
A hair _______from the scalp will exhibit stretching and damage to
the root area.
forcibly removed
41
The equipment can be used effectively for examination in various fields of forensics especially related to biological and other trace evidence like gun shot residue, metal, paints, and hair samples.
SEM-EDX/EDS
Scanning Electron Microscope (SEM)
with Energy Dispersive X-ray Spectrometer (EDX) or (EDS)
42
SEM
IMAGE FORMATION
1.____________ – surface features of an object
2.____________ – shape and size of the particles making up the object
Topography
| Morphology
43
1000 – 1,500 X
| (Image Display of hair)
MAGNIFICATION
44
The most difficult task faced by crime scene specialist is to initially locate ____ evidence at the crime scene. The search for ____ at the crime scene must be thorough, detailed and exact.
Other areas to search include the following:
Victim’s body (especially in sex crimes) _____________ and any upholstered surfaces such furniture and car seats.
Searching for Hair:
hair
hair
underneath the fingernails
45
Collection of Hair
•Hair discovered at the crime scene should be carefully removed or pick with the use of _________;
* It should be placed in a clean container, such as a ________ which should then be folded and sealed in larger envelopes. Care should be taken during folding to avoid ____ the hair. Label the outer sealed envelope.
* If a pill box is used, the entire length of the hair is in the box and it is not crushed when the lid is put on;
* If hair is attached , such as in dry blood, or caught in metal or a crack of glass, do not attempt to remove it, but rather leave hair intact on the object. If the object is small, mark it, wrap it, and seal it in an envelope. If the object is large, wrap the area containing the hair in paper to prevent loss of hairs during shipment.
fingers or a pair of tweezers
pill box, paper bindles or coin envelopes
kinking
46
determines the particular tool used in forcible entry or exit in the commission of a crime. Comparing tool marks of crime impression from the crime scene with the suspected tool found in possession of the suspect.
Tool Marks examination
47
_______ comparison of tool marks
| from the crime scene and photographs.
Microscopic
48
To restore different types of impressions such as shoe prints, foot prints and tire marks at the crime scene.
Since criminals must either walk or drive to and/or from the crime scene, it should be reasonably assumed that traces of impression evidence will be ______
Tool marks
left behind.
49
Striations from manufacturing process
Defect from use
Striations left on surface
Tool marks
50
To compare the alleged tool used in committing the crime and the standard tool mark and to compare each mark based on the characteristic striations.
Tool marks examination
51
The crime scene specialist should make a conscientious effort to thoroughly examine the scene of a crime to determine if any ______were left by the perpetrator. It is also important for the crime scene that may have been left behind. If pieces are located, they must be recovered since they can become valuable evidence when the tool and suspect are located.
SEARCHING FOR TOOL AND TOOL MARKS
•1. Searching for Tool marks –
tool marks
52
Crime Scene Specialists should ensure that they look in the following areas for potential tool marks:
```
Doors
Windows
Safes
Drawers of desks
Wire fences exhibiting cuts
Cut locks
```
53
•1. Doors- around the locking mechanisms, paying attention to the wood of the doorframe and jamb.
•2. Windows- on the bottom edge of the window, the sill and framework of the window jamb.
3. Safes-all around the door, locking mechanism and hinges.
•4. Drawers of desks, filing cabinets, or other secured drawers- Pay particular attention to the area around any locks, as well as the joining edges of each.
•5. Wire fences exhibiting cuts- compression marks from the cutting devise are often quite noticeable.
•6. Cut locks- brass locks are particularly good at retaining compression marks from the cutting tool due to the soft nature of the metal.
1
54
COLLECTING TOOL MARK EVIDENCE
Photography
Original State
Casting toolmarks
55
Before any attempt to collect toolmark evidence, it should be _____ first in its original state.
It is crucial that the toolmark is permanently recorded before any attempt is made to _______
1. Photography-
photograph
replicate or recover.
56
whenever possible, every effort be made to collect toolmark evidence in its _____.
Movable objects such as cash registers, small safes and cash boxes can be _______ by recovering the entire objects.
original state
| collected
57
If the object cannot be removed/recovered because of its size or construction, marks found on a window frame or door jamb, ________...., particularly when the home or business owner needs to replace it.
removed the damaged portion of the object
58
When it’s impractical to collect an item containing a toolmark in its entirety, _____ procedures to replicate the toolmark.
_______...will prevent the temptation to directly place recovered tools into toolmarks to verify a match. Great care should be used to ensure that the original toolmark is not damaged or altered in any manner.
Casting Toolmarks-
casting
Making casts of toolmark evidence
59
determines the characteristics and details of impression, reproduce original perishable evidence and marks in permanent objects.
Casting and Molding
60
Casting and molding
To restore different types of impressions such as ____,_____,____ at the crime scene.
shoe prints, foot prints and tire marks
61
________... is another form of valuable physical evidence that is often encountered at the crime scenes.
__________...can provide irrefutable proof of the presence of an individual or a vehicle at a crime scene or in contact with a victim.
Shoe print and tire impression evidence
impression evidence
62
Techniques of collection
Dusting with special powder
•Electrostatic lifting
•Making plastic casts
63
Tire characteristics
Class Characteristics
| Individual characteristics
64
include size and general patterns.
Class characteristics
65
include regular wear and tear as well as accidental cuts or holes.
Individual characteristics -
66
To determine the nature of the binder or the film forming polymer, the pigment and other additives.
Paint Analysis
67
Investigators encounter paint in many types of crime, including _____,______,______.
____ may be transferred and/or removed to/from an object during these incidents.
It is usually in the form of chips or smears.
hit-and-run cases, burglaries and forced entries
Paint
68
uses comparison microscope and other analytical techniques to determine (color, tint, texture, metallic dispersion, layer structure, thickness and inclusions between layers, if present).
Paint Analysis –
69
Solvent test
Micro-Fourier transform infrared spectrometry
Pyrolysis gas chromatography mass spectrometry
For organic component of paint
70
Polarized light microscopy
Visible microspectophotometry
Scanning electro microscopy-energy dispersive spectroscopy (SEM-EDS)
For Inorganic and color analysis
71
is also used to determine the binder composition of paint.
Infrared spectrophotometry
72
Paint as evidence may be collected in one of the following forms:
➢Small flakes or chips;
➢Traces of oxidized (chalking) paint;
➢Smears from fresh paint; and
➢An intact painted surface or item.
73
Paint chips may be picked up with tweezers but a preferable method is to ______ with a clean piece of paper.
In order to make a comparison, standards must be taken. When samples are collected from any painted surface, the paint should be ____ rather than scraped off. This will prevent the loss of important potential points of identification.
scoop them up
| chipped
74
Soil is analyzed to determine the _____of a criminal act, such as murder, or the path of transportation, such as a route used by drug dealers.
location
75
Soil is hugely diverse in its characteristics. By examining components of soil; such as minerals, oxides, microorganisms, fossils and other types of organic matter, a forensic scientist can determine the _______ of the sample
geography
76
Analysis of soil samples taken from vehicles can also tell an investigator about where a vehicle has been.
In the case of a vehicle, soil samples come from the interior and exterior of the front bumper and grill, wheel wells and tires, engine compartment, rock panels, tops of mufflers, the interior of the vehicle (including the trunk), rear bumper (interior and exterior), trim on the body and the windshield, and, finally, _______ the exterior of the vehicle.
swabbing
77
Aside from the elements that make up soil, forensic scientists also look for anomalies, such as ________. A simple piece of thread can link a suspect to the site of a possible struggle. In some cases, the unusual matter may actually be the soil.
glass fragments or uncharacteristic fibers
78
Soil samples when properly taken can tell an investigator a lot about where a victim or suspect has been. Analysis of ___________can also place a suspect or victim in a particular location.
A sand found inside the car can tell that the suspect has been in the beach
foot wear, clothing and tires
79
> Is a hard, brittle, amorphous substance that is composed of silicone oxides mixed with various metal oxides.
> Is a super-cooled liquid possessing high viscosity and rigidity
> Composition: fused silica + base + other elements and metal
> Types: plain, safely, wired and optical
> Visual Distinction: Color, Thickness, curvature, surface texture
glass
80
Glass _____ in response to any force that is exerted on any one of its surfaces, when the limit of elasticity is reached, the glass _______. Fractured window glass will reveal information that can be related to the force and direction of impact, which is useful in reconstructing events at a crime-scene investigation.
bends
| fractures
81
Types of Glass Fracture
Radial or primary fracture
| Concentric or secondary fracture
82
resembles the spoke of a wheel wherein the radiating rod originates at a common point
Radial or primary fracture
83
the radiating rod is being connected to one another and has a cob-web appearance.
Concentric or secondary fracture
84
Factors To Be Determined in Glass Fracture
1. Point of Impact
2. Direction of Impact or Force (Position of the Firer)
3. Age of the Fracture
4. Cause of Fracture
85
The front of the glass can be determined dust to accumulation of dust and dirt to the glass
Point of Impact
86
Direction of Impact or Force (Position of the Firer):
1. Perpendicular shot
2. Angle from the right (Right to Left)
3. Angle from the left (Left to Right)
87
exhibits an even distribution of chippings on the exit side of the glass
Perpendicular shot
88
heavy flakings or chippings on the left side of the glass
Angle from the right (Right to Left)
89
heavy flakings or chippings on the right side of the glass
Angle from the left (Left to Right)
90
age of the fracture
Fresh fracture
| Old Fracture
91
exhibits a regular pattern of radial and concentric fractures.
Fresh fracture
92
presence of a short extension lines at the end of the radial trackings
Old Fracture
93
Cause of Fracture
Due to natural means
| Due to mechanical means
94
exhibits a plain wavy lines
Due to natural means
95
exhibits a regular pattern of radial/ concentric fracture
Due to mechanical means
96
Glass exam uses ____ and other technical equipment for elemental composition analysis. Glass fractures examination determines the kind, nature, cause and age of fracture.
LA-ICP-MS
97
due to grinding and fractured edges
Chipping and flaking action
98
Glass or glass fragments are important factors in the investigation of offenses such as:
1. Burglar
2. Housebreaking
3. Fleeing the scene of vehicle accidents/ accidents, murder, assault
99
Whenever the custody of the evidence passes from one person to another, a _______ should always be obtain in order to preserve the chain of custody for court consideration.
Proper chain of custody
receipt
100
A. Properly Collected Preserved, Labeled, Packaged, and Sealed.
Physical Evidence/
| Trace Evidence
101
proper chain of custody
```
Suspect > Apprehending
Officer > Investigator
On-Case > Forensic
Examiner > Evidence
Custodian > < Forensic
Examiner > < Court
```
102
Glass and glass fragments must be ______ and their locations noted on the crime scene sketch before they are ______
photographed
touched or moved.
103
_____ must be recorded, or ______relation it has to the incident under investigation.
Pertinent date
hypothetical
104
be used for handling small fragments so as not to scratch the glass.
Rubber-tipped tweezers or Metal tweezers with adhesive tape placed over the inner surface of the points
105
Glass fragments of sufficient size are marked with a ________, . Markings are placed in an area that is of value as evidence. Markings should include your _________
diamond point or carborundum pencil a piece of properly marked adhesive tape, or a grease pencil
initials, the date, and time.
106
PRESERVATION
Glass or glass fragments should be:
wrapped in soft paper, cotton or similar material;
placed wrapped glass in a suitable container
should be properly fastened so that it will not shift
wrappings and containers should be marked “____’
Fragile
107
Extreme care should be taken to prevent further breakage of the glass during any phases of __________
Proper sample preparation and technique - obtain reliable results.
packing, shipping, or unpacking of glass shards.
108
There are seven major groups of physical evidence commonly found in a crime scene according the book published by Weston and Lushbaugh (2003).
```
Weapons
Blood
Imprints
Tool marks
Dust and dirt traces
Questioned documents
Miscellaneous trace evidence or transfer evidence
```
109
COLLECTION OF EVIDENCE
Sufficient amount of sample
Individuality/identity of sample
Labeling and markings
4. Handling of evidence with chain of custody/Transport evidence to PNP Crime Lab for appropriate forensic examinations.
110
(Physical Identification Division)
1. Ultraviolet Powder Examination
2. Bullet Trajectory Examination
3. Macro etching Examination
111
Applicable to entrapment and buy-bust operations.
uses UV Lamp to determine presence of UV fluorescent powder.
1. ULTRA-VIOLET Dusting and Exam
112
______ is the application of ultraviolet light (a type of radiation with shorter wavelength but higher in frequency than the commonly recognized on visible light) in the material to be investigated.
Ultraviolet Powder Examination
Ultraviolet Examination
113
bullet holes in glass are always wider on the _____, revealing the direction of the bullet
exit side
114
PURPOSE
A __________includes some or all of the following:
Inspection of the target surface for projectile damage
Identify entrance versus exit
Identify corresponding (ie. secondary) impact sites
Determine the directionality of the projectile path (front to back, right to left, etc.).
Measure vertical and horizontal angles of Impact
trajectory analysis
115
To determine the point of impact, position of the firearm and the probable caliber of the firearm used. Needs the use of a _________
Bullet Trajectory Exam
bullet trajectory kit.
116
process used to recover or to restore the original serial number using a strong acid solution that can dissolve metal by chemical reaction.
macro-etching
117
Articles are identified by its special peculiarity (serial number, protection number of manufacturer)
stamped, using a set of alphanumeric die, on to the metal surfaces of motor vehicle parts, firearms, valuable tools and machineries.
criminal offender will destroy this identification by erasing/defacing the serial numbers through suitable method such as chiseling, filing, grinding and filing.
_____ (restore the original numbers).
forensic examiners
118
METHODS OF SERIAL NUMBER APPLICATION
```
DOT MATRIX
LASER ENGRAVING
STAMPED NUMBER
PIN STAMPING
ENGRAVED NUMBER
EMBOSSED NUMBER
```
119
Engraved serial numbers are fairly shallow and are made by a succession of dots.
DOT MATRIX
120
Serial numbers engraved with a laser are shallow and have a “burned” appearance.
LASER ENGRAVING
121
that is pressed or punched into a metal surface.
made by using a stamp with a positive impression of a number and applying sufficient pressure to impart a negative impression of the stamp on the object
STAMPED NUMBER
122
used a single stroke, or roll, to impress a character; requires multiple strokes;
The physical aspects are the same; both result in the metal being compressed beyond its elastic limit.
The impact pin, in these machines, is driven rapidly into the metal. A rebound
mechanism will return the pin to the starting position, repeating this process.
Pin stamping machines can be driven pneumatically (air pressure) or electromagnetically (electric current)
PIN STAMPING
123
impressed intensely using electrical or mechanical gadget.
ENGRAVED NUMBER
124
raised in relief from the surface
(or produced a raised design, pattern or
lettering on a plain surface.( e.g.. metal)
EMBOSSED NUMBER
125
1. Presence of any sign of welding surrounding the serial
number;
2. Presence of several scratches and filing marks on the
metal surface where serial number is normally located;
3. Presence of any sign of concavity of the serial number
surface;
4. Presence of any difference in the style of letters and
numbers;
5. Appearance of fragmentary marks which could not be
properly identified, partly superimposed by the letters
and numbers;
6. Presence of any differences in the spacing of individual
letters and numbers
7. Misalignments of letters and numbers;8. Absence of one or more letters before in between or after a set of sequential numbers;9. Sizes and style of letters and numbers are sharper and coarser than the others;10. Presence of any irregularities in the depth of individual letters and numbers;11. Absence of rating plate;12. Model of the vehicle and the chassis number does not tally with that of the rating plate; alteration of the production number.
SPOT DETECTION OF TAMPERED SERIAL NUMBERS
126
The practice of restoring an obliterated serial number by using scientific methods.
Serial Number Restoration –
127
can provide law enforcement agencies with information about a firearm, vehicle or other item and may offer a lead in an investigation
Restoring a serial number
128
Macro-etching Exam for Motor Vehicle
Purposes:
Note: All requests for laboratory
examination shall include
the facts of the case.
1. Investigation
2. Lifting of Alarm, Re-stamping, and Verification
3. Motor Vehicle Clearance
129
Engine Number
```
Note:
Alternate Number
located at middle
portion of right
chassis
Secret Number
located ______
```
under the
| driver seat
130
Vehicle Identification
```
Vehicle Identification Number
Model Code
Engine Number
Frame / Chassis Number
Other Identification
```
131
Other Importance of Physical Identification
Establishes investigative leads
Resolves ownership issues
Strengthens filed cases in court
Proves that a crime has been committed, or establish key elements of the crime.
links a suspect to the victim or the crime scene.
Establishes the identity of persons associated with a crime.
Exonerates innocent.
Corroborate victim’s testimony.
Induces a suspect to make admissions, or even confess.
Negative evidence can help provide proof.
Physical evidence can be more reliable than eyewitness testimony.
132
Anti Carnapping Law of 1972
RA 6539
133
Anti Fencing Law of 1979
PD 1612
134
Anti Piracy and Highway
| Robbery Law of 1974
PD 532
135
Land Transportation and
| Traffic Code of 1964
RA 4136
136
a. PNP SOP No.7- Reporting and disposition of stolen and recovered/impounded motor vehicles;
b. Executive Order No. 305- Devolving to LGUs the registration of fishing vessels 3 tons and below in relation to vehicle engines used in fishing vessels and motorized bancas.
c. LGU’s Ordinances
Pertinent Laws . . . .
Government Regulations and Other Issuances
137
1. Department of Transportation and Communications (DOTC):
a. Land Transportation Office – registration and storage of MVs data through STRADCOM;
b. STRADCOM Inc. – MV data system and IT service provider;
c. Land Transportation Franchising and Regulatory Board (LTFRB) – Franchise;
d. Philippine Coast Guard (PCG) - MV shipment;
e. Philippine Ports Authority (PPA) - MV shipment
f. Maritime Industry Authority (MARINA) - MV shipment.
2. Department of the Interior and Local Government (DILG):
a. LGUs - Issuance/Cancellation of Business Permit
Registration of fishing vessels 3 tons and below.
b. NAPOLCOM - Investigate, suspend and/or dismiss PNP
personnel found to be in cahoots or abetting
carnapping.
c. Philippine National Police (PNP)
Highway Patrol Group – Lead agency in the enforcement
of RA 6539 and related laws.
Local Police Units – Assists in ANCAR operations within AOR.
Crime Laboratory – Conducts macro etching examination of Motor Vehicle
Maritime Group – Assists in the apprehension of carnapped
MVs shipped on board RORO and domestic cargo vessels.
3. Department of Justice (DOJ):
a. Prosecutors– Prosecution of carnapping cases.
b. National Bureau of Investigation (NBI) - Enforcement of RA 6539 and related laws.
c. Department of Finance (DOF)
d. Bureau of Customs (BoC) – Regulate entry of imported MVs and MV parts.
e. Insurance Commission – Set rules/guidelines on MV insurances.
Bureaucratic Procedures (Anti-Carnapping Functionaries). . . . .
138
One or more letters and numbers are being polished and grinded, and superimposed by another letters and numbers.
The metal surface bearing the original engine/chassis number is being polished, grinded and defaced.
A set of letters and numbers is stamped on the defaced metal surface.
superinmposition
139
One of the most common types of physical evidence found at a crime scene is ______, a generic term for small, often microscopic material.
In this lesson we discussed some of the types of trace evidence that a crime scene specialist will encounter at a crime scene. These include hair, fibers, tool marks, glass, paint and soil. We looked at the general properties of each one of these types of trace evidence, the value of each as evidence, and how to collect as evidence.
Throughout the lesson we learned how the various forms of trace evidence present unique detection and collection problems. We also learned that each type of evidence must be handled in a very careful and meticulous fashion to ensure not only proper collection, but also preservation for later use in criminal proceedings.
trace evidence
